If there is a poisonous one among them, the onion will turn black.
It is some of the rivers flowing into it that are poisonous.
Chemistry cannot tell us why some food is wholesome and other food is poisonous.
From this I quote the following, which is by no means the most erring and most poisonous of their shafts.
"They're just weeds and some of them might be poisonous," he ...